Seiko Cal. 6643 - 554

This Hand-Winding model from 1972 features a 41mm Hardlex-Coated Steel case. Powered by the 6643 caliber with 31j jewels beating at 28,800 bph, it delivers a 54 hours power reserve. [seikata-wm-9a487183a9ab]

Also known as: Tuna, World Timer

Specifications

Movement

Hand-Winding

Case Material

Hardlex-Coated Steel

Case Width

41mm

Case Thickness

9.7mm

Lug Width

21mm

Crystal

Mineral

Bezel

Bidirectional

Water Resistance

100m

Dial Color

Burgundy

Jewels

31j

Frequency

28,800 bph

Power Reserve

54 hours

Year

1972

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